1. Field of the Invention
The present invention relates, in general, to an electric door lock system using a cam and, more particularly, to an electric door lock system using a cam, which has a simple structure, ensures the reliability of a locking function, reduces a danger of a failure and an operation error, and is easy to fabricate and maintain, saving the cost for the fabrication and maintenance relative to the cost taken in the related art.
2. Description of the Related Art
In case of a railway train, a currently available electric door (auto door) is operated such that when a train arrives at a station, the door is opened and closed for boarding or alighting of passengers following the driver's manipulation of an actuation switch, which is performed by the driver who is seeing the passengers boarding on or alighting from the railway train.
Here, if a passenger or an object gets caught in the door during the closing of the electric door, the electric door cannot be completely closed. In this case, the driver for example is informed of such situation or information through a display or an alarm means, and the driver who recognized the state of the door being not completely closed repeatedly manipulates the actuation switch to open and close the electric door until the electric door is completely closed.
In the meantime, if the railway train is stopped to run owing to a fire, a failure, etc. of the train, or passengers should escape from the train because an emergency situation occurs in the train, the driver should directly manipulate the actuation switch to open the door after checking the state of the railway tracks, or otherwise the passengers should directly manually manipulate a manual opening/closing means, which was mounted in the proximity of the electric door, to open the door.
However, if the situation is that the railway train is running, or the state of the railway tracks is dangerous, or otherwise if nevertheless the situation is not an emergency state, the passengers can open the electric door even with their less effort, a very dangerous situation can be caused. Thus, there is a need for an electric door lock system.
In order to provide a reliable locking function, a conventional electric door lock, which was disclosed in U.S. Pat. No. 5,077,938, includes a locking roller, a locking finger member, a guide finger member, a locking roller slide channel, a roller keeper, a carriage, and the like.
However, the conventional electric door lock having the above-mentioned configuration has a problem of increased cost of fabrication and maintenance because of numerous, complex parts.